SHENZHEN/HONGKONG (Reuters) - A planned economic zone in southern China will allow full internet freedom, similar to what will be allowed in a proposed free trade zone in Shanghai, a senior official behind the project said on Thursday.

China tightly controls the internet through a so-called Great Firewall, routinely deleting online postings and blocking access to websites it deems politically sensitive or inappropriate such as Facebook and Twitter.

"In Qianhai, we will be able to see what they can see in Hong Kong," said Wang Jinxia, director of the research and innovation center of the Qianhai Authority, which is overseeing the proposed $45 billion financial zone in southern China.

"We will strive for an exclusive international communication channel in which information won't be filtered," he said, adding that Facebook and Twitter would be available.

The news is in line with a formal policy blueprint announced by China's state council, or cabinet, for Qianhai in June last year that said "a dedicated channel for international communication in Qianhai shall be supported to satisfy the needs for international communications of the enterprises in the zone".

But few details about incentives and policies within the zone, and the prospect of similar districts in Shanghai and elsewhere in China, have made some investors cautious.

The South China Morning Post said on Tuesday that social media websites such as Twitter would be accessible in a planned free trade zone in Shanghai, details of which are expected to be announced on Sunday.

The online portal of China's People's Daily said on Thursday, however, that reports of free access to foreign websites in the Shanghai zone were inaccurate.

The Qianhai official shrugged off concern that the Shanghai district would pose a challenge to its aim to become a financial and yuan hub, saying they would be mutually complementary and reform zones were needed to maintain China's development.

"We're not worried about Shanghai ... It will help promote Qianhai and shows the determination of China to reform," said Wang, who is also a spokesman for the Qianhai Authority.

Focused on finance, logistics and IT services, the Qianhai Bay economic zone hopes to draw on Hong Kong's expertise as a hub for the renminbi, or offshore yuan, as it seeks to provide the same services in renminbi, bond and equity offerings, insurance products and trade settlement.